Chicago Marathon
Race Day Weather
Cool start, mild wind shifts
Runners will face temperatures starting at 57°F and rising to 61°F, combined with an average humidity of 71%. A steady headwind from Mile 2 will challenge pacing, particularly through Miles 9-23, while tailwinds will benefit runners from Miles 1-8 and 25-26. Adjusting pace conservatively in the early miles is advisable, especially with gusts up to 22 mph creating variable conditions.
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Race Info
The Chicago Marathon starts and finishes in Grant Park, looping through 29 Chicago neighborhoods and crossing the Chicago River six times. The flat, fast course is a Boston qualifier and has produced seven marathon world records, most recently Ruth Chepng'etich's 2:09:56 women's mark in 2024. It's one of the seven Abbott World Marathon Majors, held every year on the second Sunday of October.
